Summary:
Right now the way we do BlockIter::Prev() is like this
- Go to the beginning of the restart interval
- Keep moving forward (and decoding keys using ParseNextKey()) until we reach the desired key
This can be optimized by caching the decoded entries in the first pass and reusing them in consecutive BlockIter::Prev() calls
Before caching
```
DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readreverse" --db="/dev/shm/bench_prev_opt/" --use_existing_db --disable_auto_compactions
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.413 micros/op 2423972 ops/sec; 268.2 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.414 micros/op 2413867 ops/sec; 267.0 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.410 micros/op 2440881 ops/sec; 270.0 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.414 micros/op 2417298 ops/sec; 267.4 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.413 micros/op 2421682 ops/sec; 267.9 MB/s
```
After caching
```
DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="readreverse" --db="/dev/shm/bench_prev_opt/" --use_existing_db --disable_auto_compactions
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.324 micros/op 3088955 ops/sec; 341.7 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.335 micros/op 2980999 ops/sec; 329.8 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.341 micros/op 2929681 ops/sec; 324.1 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.344 micros/op 2908490 ops/sec; 321.8 MB/s
DB path: [/dev/shm/bench_prev_opt/]
readreverse : 0.338 micros/op 2958404 ops/sec; 327.3 MB/s
```
Test Plan: COMPILE_WITH_ASAN=1 make check -j64
Reviewers: andrewkr, yiwu, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, yoshinorim
Differential Revision: https://reviews.facebook.net/D59463
Summary:
We have alot of code duplication whenever we call FullMerge we keep duplicating the instrumentation and statistics code
This is a simple diff to refactor the code to use TimedFullMerge instead of FullMerge
Test Plan: COMPILE_WITH_ASAN=1 make check -j64
Reviewers: andrewkr, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59577
Summary:
Try to decompress compressed blocks when a special flag is set.
assert and crash in debug builds if we can't decompress the just-compressed input.
Test Plan: Run unit-tests.
Reviewers: dhruba, andrewkr, sdong, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D59145
Summary: Currently, if users define both of full key bloom and prefix bloom in SST files. During Get(), if full key bloom shows the key may exist, we still go ahead and check prefix bloom. This is wasteful. If bloom filter for full keys exists, we should always ignore prefix bloom in Get().
Test Plan: Run existing tests
Reviewers: yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D57825
Summary: With `table_options.cache_index_and_filter_blocks = true`, index and filter blocks are stored in block cache. Then people are curious how much of the block cache total size is used by indexes and bloom filters. It will be nice we have a way to report that. It can help people tune performance and plan for optimized hardware setting. We add several enum values for db Statistics. BLOCK_CACHE_INDEX/FILTER_BYTES_INSERT - BLOCK_CACHE_INDEX/FILTER_BYTES_ERASE = current INDEX/FILTER total block size in bytes.
Test Plan:
write a test case called `DBBlockCacheTest.IndexAndFilterBlocksStats`. The result is:
```
[gzh@dev9927.prn1 ~/local/rocksdb] make db_block_cache_test -j64 && ./db_block_cache_test --gtest_filter=DBBlockCacheTest.IndexAndFilterBlocksStats
Makefile:101: Warning: Compiling in debug mode. Don't use the resulting binary in production
GEN util/build_version.cc
make: `db_block_cache_test' is up to date.
Note: Google Test filter = DBBlockCacheTest.IndexAndFilterBlocksStats
[==========] Running 1 test from 1 test case.
[----------] Global test environment set-up.
[----------] 1 test from DBBlockCacheTest
[ RUN ] DBBlockCacheTest.IndexAndFilterBlocksStats
[ OK ] DBBlockCacheTest.IndexAndFilterBlocksStats (689 ms)
[----------] 1 test from DBBlockCacheTest (689 ms total)
[----------] Global test environment tear-down
[==========] 1 test from 1 test case ran. (689 ms total)
[ PASSED ] 1 test.
```
Reviewers: IslamAbdelRahman, andrewkr, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D58677
Summary: Deprecate this one option and delete code and tests that are now superfluous.
Test Plan: all tests pass
Reviewers: igor, yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: msalib, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D55317
Summary:
Added a new abstraction to cache page to RocksDB designed for the read
cache use.
RocksDB current block cache is more of an object cache. For the persistent read cache
project, what we need is a page cache equivalent. This changes adds a cache
abstraction to RocksDB to cache pages called PersistentCache. PersistentCache can cache
uncompressed pages or raw pages (content as in filesystem). The user can
choose to operate PersistentCache either in COMPRESSED or UNCOMPRESSED mode.
Blame Rev:
Test Plan: Run unit tests
Reviewers: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D55707
Summary: Store SST file compression algorithm as a TableProperty.
Test Plan: Modified and ran the table_test UT that checks for TableProperties
Reviewers: IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: lgalanis, andrewkr, dhruba, IslamAbdelRahman
Differential Revision: https://reviews.facebook.net/D58017
Summary: This is to provide a way for users to skip prefix bloom in point look-up.
Test Plan: Add a new unit test scenario.
Reviewers: IslamAbdelRahman
Subscribers: leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D57747
Summary:
This adds a new metablock containing a shared dictionary that is used
to compress all data blocks in the SST file. The size of the shared dictionary
is configurable in CompressionOptions and defaults to 0. It's currently only
used for zlib/lz4/lz4hc, but the block will be stored in the SST regardless of
the compression type if the user chooses a nonzero dictionary size.
During compaction, computes the dictionary by randomly sampling the first
output file in each subcompaction. It pre-computes the intervals to sample
by assuming the output file will have the maximum allowable length. In case
the file is smaller, some of the pre-computed sampling intervals can be beyond
end-of-file, in which case we skip over those samples and the dictionary will
be a bit smaller. After the dictionary is generated using the first file in a
subcompaction, it is loaded into the compression library before writing each
block in each subsequent file of that subcompaction.
On the read path, gets the dictionary from the metablock, if it exists. Then,
loads that dictionary into the compression library before reading each block.
Test Plan: new unit test
Reviewers: yhchiang, IslamAbdelRahman, cyan, sdong
Reviewed By: sdong
Subscribers: andrewkr, yoshinorim, kradhakrishnan, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52287
Summary:
While trying to reuse PinData() / ReleasePinnedData() .. to optimize away some memcpys I realized that there is a significant overhead for using PinData() / ReleasePinnedData if they were called many times.
This diff refactor the pinning logic by introducing PinnedIteratorsManager a centralized component that will be created once and will be notified whenever we need to Pin an Iterator. This implementation have much less overhead than the original implementation
Test Plan:
make check -j64
COMPILE_WITH_ASAN=1 make check -j64
Reviewers: yhchiang, sdong, andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56493
Summary:
This is the original diff that I have landed and reverted and now I want to land again https://reviews.facebook.net/D34269
For old SST files we will show
```
comparator name: N/A
merge operator name: N/A
property collectors names: N/A
```
For new SST files with no merge operator name and with no property collectors
```
comparator name: leveldb.BytewiseComparator
merge operator name: nullptr
property collectors names: []
```
for new SST files with these properties
```
comparator name: leveldb.BytewiseComparator
merge operator name: UInt64AddOperator
property collectors names: [DummyPropertiesCollector1,DummyPropertiesCollector2]
```
Test Plan: unittests
Reviewers: andrewkr, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56487
Comparable with Snappy on comp ratio.
Implemented using Windows API, does not require external package.
Avaiable since Windows 8 and server 2012.
Use -DXPRESS=1 with CMake to enable.
Summary:
In the case where we can't find a filter block, there is not much benefit of doing the binary search and see whether the index key has the prefix. With the change, we blindly return true if we can't get the filter.
It also fixes missing row cases for reverse comparator with full bloom.
Test Plan: Add a test case that used to fail.
Reviewers: yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: kradhakrishnan, yiwu, hermanlee4, yoshinorim, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56697
Summary:
Full block checking should be a good enough indication of prefix existance. No need to further check data block.
This also fixes wrong results when using prefix bloom and reverse bitwise comparator.
Test Plan: Will add a unit test.
Reviewers: yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: hermanlee4, yoshinorim, yiwu, kradhakrishnan, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56625
Summary: PrefixTest.PrefixAndWholeKeyTest runs against the same directory as prefix_test, which sometimes fail parallel tests. Fix it.
Test Plan: Run it in parallel and see it doesn't fail anymore.
Reviewers: andrewkr
Reviewed By: andrewkr
Subscribers: leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56541
Summary: Cache shard bit 4 is sometimes too small and 6 is a more common value picked by users. Make that default. It shouldn't hurt much to change options.max_file_opening_threads default to be 16, which will reduce the worst case DB open time.
Test Plan: Run all existing tests.
Reviewers: IslamAbdelRahman, yhchiang, kradhakrishnan, igor, andrewkr
Reviewed By: andrewkr
Subscribers: andrewkr, MarkCallaghan, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D55047
Summary:
Added the column family name to the properties block. This property
is omitted only if the property is unavailable, such as when RepairDB()
writes SST files.
In a next diff, I will change RepairDB to use this new property for
deciding to which column family an existing SST file belongs. If this
property is missing, it will add it to the "unknown" column family (same
as its existing behavior).
Test Plan:
New unit test:
$ ./db_table_properties_test --gtest_filter=DBTablePropertiesTest.GetColumnFamilyNameProperty
Reviewers: IslamAbdelRahman, yhchiang, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D55605
Summary:
When a block based table file is opened, if prefetch_index_and_filter is true, it will prefetch the index and filter blocks, putting them into the block cache.
What this feature adds: when a L0 block based table file is opened, if pin_l0_filter_and_index_blocks_in_cache is true in the options (and prefetch_index_and_filter is true), then the filter and index blocks aren't released back to the block cache at the end of BlockBasedTableReader::Open(). Instead the table reader takes ownership of them, hence pinning them, ie. the LRU cache will never push them out. Meanwhile in the table reader, further accesses will not hit the block cache, thus avoiding lock contention.
Test Plan:
'export TEST_TMPDIR=/dev/shm/ && DISABLE_JEMALLOC=1 OPT=-g make all valgrind_check -j32' is OK.
I didn't run the Java tests, I don't have Java set up on my devserver.
Reviewers: sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56133
Summary:
Expose the inverse of ToString(hex=true) on Slice: Slice::DecodeHex
Refactor the other implementation of to/from hex in ldb_cmd.h to use the Slice
version
(Difference between the 2 is whether 0x is expected/produced in front of the hex
string or not)
Eliminated support for invalid odd length hex string - this is now invalid
instead of having 1/2 byte set
Added (inverse of HexToString) test for LDBCommand::StringToHex which also
indirectly tests Slice::ToString(true)
After moving the original implementation from ldb_cmd.h, updated it to much simpler/efficient version
(originally/inspired from https://github.com/facebook/wdt/blob/master/util/EncryptionUtils.cpp#L140-L169 )
Test Plan: run tests
Reviewers: uddipta, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D56121
Summary:
When a block based table file is opened, if prefetch_index_and_filter is true, it will prefetch the index and filter blocks, putting them into the block cache.
What this feature adds: when a L0 block based table file is opened, if pin_l0_filter_and_index_blocks_in_cache is true in the options (and prefetch_index_and_filter is true), then the filter and index blocks aren't released back to the block cache at the end of BlockBasedTableReader::Open(). Instead the table reader takes ownership of them, hence pinning them, ie. the LRU cache will never push them out. Meanwhile in the table reader, further accesses will not hit the block cache, thus avoiding lock contention.
When the table reader is destroyed, it releases the pinned blocks (if there were any). This has to happen before the cache is destroyed, so I had to introduce a TableReader::Close(), to guarantee the order of destruction.
Test Plan:
Added two unit tests for this. Existing unit tests run fine (default is pin_l0_filter_and_index_blocks_in_cache=false).
DISABLE_JEMALLOC=1 OPT=-g make all valgrind_check -j32
Mac: OK.
Linux: with D55287 patched in it's OK.
Reviewers: sdong
Reviewed By: sdong
Subscribers: andrewkr, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D54801
Summary:
In block based table reader, wow we put index reader to block cache, which can be retrieved after DB restart. However, index reader may reference internal comparator, which can be destroyed after DB restarts, causing problems.
Fix it by making cache key identical per table reader.
Test Plan: Add a new test which failed with out the commit but now pass.
Reviewers: IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: maro, yhchiang, kradhakrishnan, leveldb, andrewkr, dhruba
Differential Revision: https://reviews.facebook.net/D55287
Summary:
Cache to have an option to fail Cache::Insert() when full. Update call sites to check status and handle error.
I totally have no idea what's correct behavior of all the call sites when they encounter error. Please let me know if you see something wrong or more unit test is needed.
Test Plan: make check -j32, see tests pass.
Reviewers: anthony, yhchiang, andrewkr, IslamAbdelRahman, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: andrewkr, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D54705
Summary: We want to provide a way to detect whether an iterator is stale and needs to be recreated. Add a iterator property to return version number.
Test Plan: Add two unit tests for it.
Reviewers: IslamAbdelRahman, yhchiang, anthony, kradhakrishnan, andrewkr
Reviewed By: andrewkr
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D54921
Summary:
Add Iterator::GetProperty(), a way for users to communicate with iterator, and turn Iterator::IsKeyPinned() with it.
As a follow-up, I'll ask a property as the version number attached to the iterator
Test Plan: Rerun existing tests and add a negative test case.
Reviewers: yhchiang, andrewkr, kradhakrishnan, anthony, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D54783
Summary:
This reverts commit 73c31377bb, which mistakenly
reverts 73c31377bb that fixes a bug when both
whole_key_filtering and prefix_extractor are set
Test Plan: revert the patch
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D52707
Summary:
Add kSstFileTier to ReadTier, which allows Get and MultiGet to
read only directly from SST files and skip mem-tables.
kSstFileTier = 0x2 // data in SST files.
// Note that this ReadTier currently only supports
// Get and MultiGet and does not support iterators.
Test Plan: add new test in db_test.
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: igor, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D53511
Summary: Add a new option to BlockBasedTableOptions that will allow us to change the restart interval for the index block
Test Plan: unit tests
Reviewers: yhchiang, anthony, andrewkr, sdong
Reviewed By: sdong
Subscribers: march, dhruba
Differential Revision: https://reviews.facebook.net/D53721
Summary: Similar to D53385 we need to check InDomain before checking the filter block.
Test Plan: unit tests
Reviewers: yhchiang, rven, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D53421
Summary:
Right now when we are creating a BlockBasedTable with fill filter block
we add to the filter all the prefixes that are InDomain() based on the prefix_extractor
the problem is that when we read a key from the file, we check the filter block for the prefix whether or not it's InDomain()
Test Plan: unit tests
Reviewers: yhchiang, rven, anthony, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D53385
Summary:
SstFileWriter may create an sst file with no entries
Right now this will fail when being ingested using DB::AddFile() saying that the keys are corrupted
Test Plan: make check
Reviewers: yhchiang, rven, anthony, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52815
Summary:
After introducing Iterator::PinData(), we have extra overhead of deleting the pinned iterators that we track in a std::set
This patch avoid inserting to the std::set if we have only one iterator (normal use case when no iterators are pinned)
Before this change
```
DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="newiterator" --db="/tmp/rocksdbtest-8616/dbbench" --use_existing_db --disable_auto_compactions
newiterator : 1.006 micros/op 994013 ops/sec;
newiterator : 0.994 micros/op 1006295 ops/sec;
newiterator : 0.990 micros/op 1010422 ops/sec;
```
After change
```
DEBUG_LEVEL=0 make db_bench -j64 && ./db_bench --benchmarks="newiterator" --db="/tmp/rocksdbtest-8616/dbbench" --use_existing_db --disable_auto_compactions
newiterator : 0.754 micros/op 1326588 ops/sec;
newiterator : 0.759 micros/op 1317394 ops/sec;
newiterator : 0.691 micros/op 1446704 ops/sec;
```
Test Plan: make check -j64
Reviewers: yhchiang, rven, anthony, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52761
Summary: <array> is not included in table/plain_table_key_coding.h. It may be the cause of one CLANG build failure.
Test Plan: Build it
Reviewers: yhchiang, rven, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D52725
Summary: In plain table reader's non-mmap mode, we only keep the most recent read buffer. However, for binary search, it is likely we come back to a location to read. To avoid one pread in such a case, we keep two read buffers. It should cover most of the cases.
Test Plan:
1. run tests
2. check the optimization works through strace when running
./table_reader_bench -mmap_read=false --num_keys2=1 -num_keys1=5000 -table_factory=plain_table --iterator --through_db
Reviewers: anthony, rven, kradhakrishnan, igor, yhchiang, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D51171
Summary:
table_test is failing because we are creating a temp InternalComparator
14:27:28 [ RUN ] BlockBasedTableTest.NoopTransformSeek
14:27:28 pure virtual method called
14:27:28 terminate called without an active exception
14:27:28 /bin/sh: line 7: 2346261 Aborted (core dumped) ./$t
Test Plan: make table_test -j64 && ./table_test --gtest_filter="BlockBasedTableTest.NoopTransformSeek"
Reviewers: igor, sdong, anthony, rven
Reviewed By: rven
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52671
Summary:
This patch reverts commit 57605d7ef3 as it will
cause BlockBasedTableTest.NoopTransformSeek test crashes in some environment.
Test Plan: revert the patch
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52623
Summary:
When both whole_key_filtering and prefix_extractor are set, RocksDB will
mistakenly encode prefix + whole key into the database instead of
simply whole key when BlockBasedTable is used. This patch fixes this bug.
Test Plan: Add a test in table_test
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D52233
Summary: DBImpl::GetLatestSequenceForKey() can do memcpy's to load a value that will never be used. This can be optimized by changing all the Get() functions called to optionally not fetch the value (and only fetch the sequencenumber).
Test Plan: optimistic_transaction_test and transaction_test
Reviewers: anthony
Reviewed By: anthony
Subscribers: leveldb, dhruba, hermanlee4
Differential Revision: https://reviews.facebook.net/D52227
PrefixMayMatch previously seeked in the prefix index using an internal
key with a sequence number of 0. This would cause the prefix index seek
to fall off the end if the last key in the index had a user-key greater
than or equal to the key being looked for. Falling off the end of the
index in turn results in PrefixMayMatch returning false if the index is
in memory.
Summary: If block_restart_interval gets set to less than 1 an assert will be triggered in BlockBuilder::BlockBuilder(). This prevents the user from doing this by silently setting any value less than 1 to 1.
Test Plan: Added a test (in BlockBasedTableTest in table_test) that checks invalid values to make sure that they are reset to the expected values. The block_restart_interval value is checked along with block_size_deviation which also silently sets the value if it is outside a specific range.
Reviewers: yoshinorim, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52509
Summary:
myrocks seems to build rocksdb using
-Wmissing-field-initializers (and treats warnings as errors). This diff
adds that flag to the rocksdb build, and fixes the compilation failures
that result. I have not checked for any other differences in the build
flags for rocksdb build as part of myrocks.
Test Plan: make check
Reviewers: sdong, rven
Reviewed By: rven
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52443
Summary:
This diff adds support for concurrent adds to the skiplist memtable
implementations. Memory allocation is made thread-safe by the addition of
a spinlock, with small per-core buffers to avoid contention. Concurrent
memtable writes are made via an additional method and don't impose a
performance overhead on the non-concurrent case, so parallelism can be
selected on a per-batch basis.
Write thread synchronization is an increasing bottleneck for higher levels
of concurrency, so this diff adds --enable_write_thread_adaptive_yield
(default off). This feature causes threads joining a write batch
group to spin for a short time (default 100 usec) using sched_yield,
rather than going to sleep on a mutex. If the timing of the yield calls
indicates that another thread has actually run during the yield then
spinning is avoided. This option improves performance for concurrent
situations even without parallel adds, although it has the potential to
increase CPU usage (and the heuristic adaptation is not yet mature).
Parallel writes are not currently compatible with
inplace updates, update callbacks, or delete filtering.
Enable it with --allow_concurrent_memtable_write (and
--enable_write_thread_adaptive_yield). Parallel memtable writes
are performance neutral when there is no actual parallelism, and in
my experiments (SSD server-class Linux and varying contention and key
sizes for fillrandom) they are always a performance win when there is
more than one thread.
Statistics are updated earlier in the write path, dropping the number
of DB mutex acquisitions from 2 to 1 for almost all cases.
This diff was motivated and inspired by Yahoo's cLSM work. It is more
conservative than cLSM: RocksDB's write batch group leader role is
preserved (along with all of the existing flush and write throttling
logic) and concurrent writers are blocked until all memtable insertions
have completed and the sequence number has been advanced, to preserve
linearizability.
My test config is "db_bench -benchmarks=fillrandom -threads=$T
-batch_size=1 -memtablerep=skip_list -value_size=100 --num=1000000/$T
-level0_slowdown_writes_trigger=9999 -level0_stop_writes_trigger=9999
-disable_auto_compactions --max_write_buffer_number=8
-max_background_flushes=8 --disable_wal --write_buffer_size=160000000
--block_size=16384 --allow_concurrent_memtable_write" on a two-socket
Xeon E5-2660 @ 2.2Ghz with lots of memory and an SSD hard drive. With 1
thread I get ~440Kops/sec. Peak performance for 1 socket (numactl
-N1) is slightly more than 1Mops/sec, at 16 threads. Peak performance
across both sockets happens at 30 threads, and is ~900Kops/sec, although
with fewer threads there is less performance loss when the system has
background work.
Test Plan:
1. concurrent stress tests for InlineSkipList and DynamicBloom
2. make clean; make check
3. make clean; DISABLE_JEMALLOC=1 make valgrind_check; valgrind db_bench
4. make clean; COMPILE_WITH_TSAN=1 make all check; db_bench
5. make clean; COMPILE_WITH_ASAN=1 make all check; db_bench
6. make clean; OPT=-DROCKSDB_LITE make check
7. verify no perf regressions when disabled
Reviewers: igor, sdong
Reviewed By: sdong
Subscribers: MarkCallaghan, IslamAbdelRahman, anthony, yhchiang, rven, sdong, guyg8, kradhakrishnan, dhruba
Differential Revision: https://reviews.facebook.net/D50589
Summary:
When Get() or NewIterator() trigger file loads, skip caching the filter block if
(1) optimize_filters_for_hits is set and (2) the file is on the bottommost
level. Also skip checking filters under the same conditions, which means that
for a preloaded file or a file that was trivially-moved to the bottom level, its
filter block will eventually expire from the cache.
- added parameters/instance variables in various places in order to propagate the config ("skip_filters") from version_set to block_based_table_reader
- in BlockBasedTable::Rep, this optimization prevents filter from being loaded when the file is opened simply by setting filter_policy = nullptr
- in BlockBasedTable::Get/BlockBasedTable::NewIterator, this optimization prevents filter from being used (even if it was loaded already) by setting filter = nullptr
Test Plan:
updated unit test:
$ ./db_test --gtest_filter=DBTest.OptimizeFiltersForHits
will also run 'make check'
Reviewers: sdong, igor, paultuckfield, anthony, rven, kradhakrishnan, IslamAbdelRahman, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb
Differential Revision: https://reviews.facebook.net/D51633
Summary:
I added this line in my previous patch D48999 (which is incorrect)
We should not release the iterator since releasing it will evict the blocks from cache
Test Plan:
Run the test under valgrind
make check
Reviewers: rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D52161
Summary:
This patch update the Iterator API to introduce new functions that allow users to keep the Slices returned by key() valid as long as the Iterator is not deleted
ReadOptions::pin_data : If true keep loaded blocks in memory as long as the iterator is not deleted
Iterator::IsKeyPinned() : If true, this mean that the Slice returned by key() is valid as long as the iterator is not deleted
Also add a new option BlockBasedTableOptions::use_delta_encoding to allow users to disable delta_encoding if needed.
Benchmark results (using https://phabricator.fb.com/P20083553)
```
// $ du -h /home/tec/local/normal.4K.Snappy/db10077
// 6.1G /home/tec/local/normal.4K.Snappy/db10077
// $ du -h /home/tec/local/zero.8K.LZ4/db10077
// 6.4G /home/tec/local/zero.8K.LZ4/db10077
// Benchmarks for shard db10077
// _build/opt/rocks/benchmark/rocks_copy_benchmark \
// --normal_db_path="/home/tec/local/normal.4K.Snappy/db10077" \
// --zero_db_path="/home/tec/local/zero.8K.LZ4/db10077"
// First run
// ============================================================================
// rocks/benchmark/RocksCopyBenchmark.cpp relative time/iter iters/s
// ============================================================================
// BM_StringCopy 1.73s 576.97m
// BM_StringPiece 103.74% 1.67s 598.55m
// ============================================================================
// Match rate : 1000000 / 1000000
// Second run
// ============================================================================
// rocks/benchmark/RocksCopyBenchmark.cpp relative time/iter iters/s
// ============================================================================
// BM_StringCopy 611.99ms 1.63
// BM_StringPiece 203.76% 300.35ms 3.33
// ============================================================================
// Match rate : 1000000 / 1000000
```
Test Plan: Unit tests
Reviewers: sdong, igor, anthony, yhchiang, rven
Reviewed By: rven
Subscribers: dhruba, lovro, adsharma
Differential Revision: https://reviews.facebook.net/D48999
Summary:
Currently, transactions can fail even if there is no actual write conflict. This is due to relying on only the memtables to check for write-conflicts. Users have to tune memtable settings to try to avoid this, but it's hard to figure out exactly how to tune these settings.
With this diff, TransactionDB will use both memtables and SST files to determine if there are any write conflicts. This relies on the fact that BlockBasedTable stores sequence numbers for all writes that happen after any open snapshot. Also, D50295 is needed to prevent SingleDelete from disappearing writes (the TODOs in this test code will be fixed once the other diff is approved and merged).
Note that Optimistic transactions will still rely on tuning memtable settings as we do not want to read from SST while on the write thread. Also, memtable settings can still be used to reduce how often TransactionDB needs to read SST files.
Test Plan: unit tests, db bench
Reviewers: rven, yhchiang, kradhakrishnan, IslamAbdelRahman, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb, yoshinorim
Differential Revision: https://reviews.facebook.net/D50475
Summary: In non-mmap mode, plain table reader can issue two pread() for index checking and reading the actual data, although it's for the same location. By reusing the key decoder, we reuse the buffer used for the two to avoid it.
Test Plan: Run unit tests. Run table_reader_bench and see from strace the repeat read cases to disappear.
Reviewers: anthony, yhchiang, rven, kradhakrishnan, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D50949
Summary:
The commit of option helper refactor broken the build:
(1) a git merge problem
(2) some uncaught compiler warning
Fix it.
Test Plan: Make sure "make all" passes
Reviewers: anthony, IslamAbdelRahman, rven, kradhakrishnan, yhchiang
Reviewed By: yhchiang
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D50943
Summary:
This patch adds OptionsUtil::LoadOptionsFromFile() and
OptionsUtil::LoadLatestOptionsFromDB(), which allow developers
to construct DBOptions and ColumnFamilyOptions from a RocksDB
options file. Note that most pointer-typed options such as
merge_operator will not be constructed.
With this API, developers no longer need to remember all the
options in order to reopen an existing rocksdb instance like
the following:
DBOptions db_options;
std::vector<std::string> cf_names;
std::vector<ColumnFamilyOptions> cf_opts;
// Load primitive-typed options from an existing DB
OptionsUtil::LoadLatestOptionsFromDB(
dbname, &db_options, &cf_names, &cf_opts);
// Initialize necessary pointer-typed options
cf_opts[0].merge_operator.reset(new MyMergeOperator());
...
// Construct the vector of ColumnFamilyDescriptor
std::vector<ColumnFamilyDescriptor> cf_descs;
for (size_t i = 0; i < cf_opts.size(); ++i) {
cf_descs.emplace_back(cf_names[i], cf_opts[i]);
}
// Open the DB
DB* db = nullptr;
std::vector<ColumnFamilyHandle*> cf_handles;
auto s = DB::Open(db_options, dbname, cf_descs,
&handles, &db);
Test Plan:
Augment existing tests in column_family_test
options_test
db_test
Reviewers: igor, IslamAbdelRahman, sdong, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D49095
Summary:
Reverting https://reviews.facebook.net/D34269 for now
after I landed it a flaky test started continuously failing, I am almost sure this patch is not related to the test but I will revert it until I figure out why it's failing
Test Plan: make check
Reviewers: kradhakrishnan
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D50385
Enable C4307 'operator' : integral constant overflow
Longs and ints on Windows are 32-bit hence the overflow
Enable C4309 'conversion' : truncation of constant value
Enable C4512 'class' : assignment operator could not be generated
Enable C4701 Potentially uninitialized local variable 'name' used
Summary:
This diff introduce new table properties that will be written for block based tables
These properties are
- comparator name
- merge operator name
- property collectors names
Test Plan:
- Added a new unit test to verify that these tests are written/read correctly
- Running all other tests right now (wont land until all tests finish)
Reviewers: rven, kradhakrishnan, igor, sdong, anthony, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D34269
On Windows two tests fail that use MockTable:
flush_job_test and compaction_job_test with the following message:
compaction_job_test_je.exe : Assertion failed: result.size() == 4,
file c:\dev\rocksdb\rocksdb\table\mock_table.cc, line 110
Investigation reveals that this failure occurs when a 4 byte
ID written to a beginning of the physically open file (main
contents remains in a in-memory map) can not be read back.
The reason for the failure is that the ID is written directly
to a WritableFile bypassing WritableFileWriter. The side effect of that
is that pending_sync_ never becomes true so the file is never flushed,
however, the direct cause of the failure is that the filesize_ member
of the WritableFileWriter remains zero. At Close() the file is truncated
to that size and the file becomes empty so the ID can not be read back.
Summary:
We are cleaning up dependencies.
This diff takes a first step at moving memtable files to their own
directory called memtable. In future diffs, we will move other memtable
files from db to memtable.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D48915
Summary:
Separate a new class InternalIterator from class Iterator, when the look-up is done internally, which also means they operate on key with sequence ID and type.
This change will enable potential future optimizations but for now InternalIterator's functions are still the same as Iterator's.
At the same time, separate the cleanup function to a separate class and let both of InternalIterator and Iterator inherit from it.
Test Plan: Run all existing tests.
Reviewers: igor, yhchiang, anthony, kradhakrishnan, IslamAbdelRahman, rven
Reviewed By: rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48549
Summary:
Fix tests that compile under ROCKSDB_LITE but currently failing.
table_test:
RandomizedLongDB test is using internal stats which is not supported in ROCKSDB_LITE
compaction_job_test:
Using CompactionJobStats which is not supported
perf_context_test:
KeyComparisonCount test try to open DB in ReadOnly mode which is not supported
Test Plan: run the tests under ROCKSDB_LITE
Reviewers: yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48585
Summary: It would be nice to have and access to table properties in compaction callbacks. In MyRocks project, it will make possible to update optimizer statistics online.
Test Plan: ran the unit test. Ran myrocks with the new way of collecting stats.
Reviewers: igor, rven, yhchiang
Reviewed By: yhchiang
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48267
Summary: Pass column family ID through TablePropertiesCollectorFactory::CreateTablePropertiesCollector() so that users can identify which column family this file is for and handle it differently.
Test Plan: Add unit test scenarios in tests related to table properties collectors to verify the information passed in is correct.
Reviewers: rven, yhchiang, anthony, kradhakrishnan, igor, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: yoshinorim, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D48411
Summary: Add 2 new counters BLOCK_CACHE_BYTES_WRITE, BLOCK_CACHE_BYTES_READ to keep track of how many bytes were written to the cache and how many bytes that we read from cache
Test Plan: make check
Reviewers: sdong, yhchiang, igor
Reviewed By: igor
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D48195
Summary:
hit and miss bloom filter stats for memtable and SST
stats added to perf_context struct
key matches and prefix matches combined into one stat
Test Plan: unit test veryfing the functionality added, see BloomStatsTest in db_test.cc for details
Reviewers: yhchiang, igor, sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D47859
Summary:
Since Andres' internship is over, I took over https://reviews.facebook.net/D42555 and rebased and simplified it a bit.
The behavior in this diff is a bit simpler than in D42555:
* only merge operators are passed through FilterMergeValue(). If fitler function returns true, the merge operator is ignored
* compaction filter is *not* called on: 1) results of merge operations and 2) base values that are getting merged with merge operands (the second case was also true in previous diff)
Do we also need a compaction filter to get called on merge results?
Test Plan: make && make check
Reviewers: lovro, tnovak, rven, yhchiang, sdong
Reviewed By: sdong
Subscribers: noetzli, kolmike, leveldb, dhruba, sdong
Differential Revision: https://reviews.facebook.net/D47847
Summary: Recent patch introduced a bug that if non-mmap mode is used, in prefix encoding case, there is a resizing of cur_key_ within the same prefix, we still read prefix from the released buffer. It fails ASAN tests and this commit fixes it.
Test Plan: Run the ASAN tests for the failing test case.
Reviewers: IslamAbdelRahman, yhchiang, anthony, igor, kradhakrishnan, rven
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D47457
Summary:
This is an initial version of bulk load feature
This diff allow us to create sst files, and then bulk load them later, right now the restrictions for loading an sst file are
(1) Memtables are empty
(2) Added sst files have sequence number = 0, and existing values in database have sequence number = 0
(3) Added sst files values are not overlapping
Test Plan: unit testing
Reviewers: igor, ott, sdong
Reviewed By: sdong
Subscribers: leveldb, ott, dhruba
Differential Revision: https://reviews.facebook.net/D39081
Summary:
PlainTableReader now only allows mmap-mode. Add the support to non-mmap mode for more flexibility.
Refactor the codes to move all logic of reading data to PlainTableKeyDecoder, and consolidate the calls to Read() call and ReadVarint32() call. Implement the calls for both of mmap and non-mmap case seperately. For non-mmap mode, make copy of keys in several places when we need to move the buffer after reading the keys.
Test Plan: Add the mode of non-mmap case in plain_table_db_test. Run it in valgrind mode too.
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D47187
Summary: RandomAccessFileReader unnecessarily inherited RandomAccessFile, which can introduce unnecessarily extra costs. Remove it.
Test Plan: Run all existing tests
Reviewers: yhchiang, anthony, igor, kradhakrishnan, rven, IslamAbdelRahman
Reviewed By: IslamAbdelRahman
Subscribers: leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D47409
Summary:
This patch fixes#7460559. It introduces SingleDelete as a new database
operation. This operation can be used to delete keys that were never
overwritten (no put following another put of the same key). If an overwritten
key is single deleted the behavior is undefined. Single deletion of a
non-existent key has no effect but multiple consecutive single deletions are
not allowed (see limitations).
In contrast to the conventional Delete() operation, the deletion entry is
removed along with the value when the two are lined up in a compaction. Note:
The semantics are similar to @igor's prototype that allowed to have this
behavior on the granularity of a column family (
https://reviews.facebook.net/D42093 ). This new patch, however, is more
aggressive when it comes to removing tombstones: It removes the SingleDelete
together with the value whenever there is no snapshot between them while the
older patch only did this when the sequence number of the deletion was older
than the earliest snapshot.
Most of the complex additions are in the Compaction Iterator, all other changes
should be relatively straightforward. The patch also includes basic support for
single deletions in db_stress and db_bench.
Limitations:
- Not compatible with cuckoo hash tables
- Single deletions cannot be used in combination with merges and normal
deletions on the same key (other keys are not affected by this)
- Consecutive single deletions are currently not allowed (and older version of
this patch supported this so it could be resurrected if needed)
Test Plan: make all check
Reviewers: yhchiang, sdong, rven, anthony, yoshinorim, igor
Reviewed By: igor
Subscribers: maykov, dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D43179
Summary: Missed one file in the previous commit
Test Plan: compiles
Reviewers: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D47055
Summary:
Refactoring NewTableReader to accept TableReaderOptions
This will make it easier to add new options in the future, for example in this diff https://reviews.facebook.net/D46071
Test Plan: run existing tests
Reviewers: igor, yhchiang, anthony, rven, sdong
Reviewed By: sdong
Subscribers: dhruba
Differential Revision: https://reviews.facebook.net/D46179
Summary:
In some cases, equality comparisons can be done more efficiently than three-way
comparisons. There are quite a few places in the code where we only care about
equality. This patch adds an Equal() method that defaults to using the
Compare() method.
Test Plan: make clean all check
Reviewers: rven, anthony, yhchiang, igor, sdong
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D46233
Summary:
This optimizes the case when (cache_index_and_filter_blocks=1) and bloom filter is not present in the cache.
Previously we did:
1. Read meta block from file
2. Read the filter position from the meta block
3. Read the filter
Now, we pre-load the filter position on Table::Open(), so we can skip steps (1) and (2) on bloom filter cache miss. Instead of 2 IOs, we do only 1.
Test Plan: make check
Reviewers: sdong
Reviewed By: sdong
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D46047
Summary:
This diff is a collection of cleanups that were initially part of D43179.
Additionally it adds a unified way of defining key-value maps that use a
Comparator for sorting (this was previously implemented in four different
places).
Test Plan: make clean check all
Reviewers: rven, anthony, yhchiang, sdong, igor
Reviewed By: igor
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45993
Summary: Add ZSTD compression type. The same way as adding LZ4.
Test Plan: run all tests. Generate files in db_bench. Make sure reads succeed. But the SST files cannot be opened in older versions. Also some other adhoc tests.
Reviewers: rven, anthony, IslamAbdelRahman, kradhakrishnan, igor
Reviewed By: igor
Subscribers: MarkCallaghan, maykov, yoshinorim, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D45747
Summary:
This patch adds "rocksdb.aggregated-table-properties"
and "rocksdb.aggregated-table-properties-at-levelN", the former
returns the aggreated table properties of a column family,
while the later returns the aggregated table properties
of the specified level N.
Test Plan: Added tests in db_test
Reviewers: igor, sdong, IslamAbdelRahman, anthony
Reviewed By: anthony
Subscribers: dhruba, leveldb
Differential Revision: https://reviews.facebook.net/D45087
Summary: Add more test cases of data race causing wrong iterating results. Tag tests not passing as DISABLED_
Test Plan: Run the tests
Reviewers: igor, rven, IslamAbdelRahman, anthony, kradhakrishnan, yhchiang
Reviewed By: yhchiang
Subscribers: tnovak, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D44907
Summary: Iterator has a bug: if a child iterator reaches its end, and user issues a Prev(), and just before SeekToLast() of the child iterator is called, some extra rows is added in the end, the position of iterator can be misplaced.
Test Plan: Run the tests with or without valgrind
Reviewers: rven, yhchiang, IslamAbdelRahman, anthony
Reviewed By: anthony
Subscribers: tnovak, leveldb, dhruba
Differential Revision: https://reviews.facebook.net/D43671
